I like this definition of an affair -- it brings together the three key elements: a secretive relationship, which is the core structure of an affair;

我倾向于这样来定义婚外情， 它包含三个要素： 首先是遮遮掩掩的关系， 这是婚外情的核心；

youdao

This is a HUGE step for them since they both are so secretive about their relationship.

考虑到他们一直都对这段感情秘而不宣，这次同走红毯算是前进了巨大的一步。

youdao

It's true that women love excitement, especially in a new relationship, and there is no better way to keep that excitement alive than being slightly secretive.

在一段全新的关系中，女人容易爱激动这是事实，但要保持这样的激情最好的办法是留有一些秘密。

youdao

Mr. Robinson's relationship with Mr. Kluger, on the other hand, was more secretive, according to Mr. Robinson and the complaint.

WSJ: The Confessions of an Inside Trader